Centrifugal fan.



s. 0; DAVIDSON.

GENTRIIUGAL FAN. APPLICATION FILED MAY 23, 1913.

Patented Sept. 22, 1914.

2 SHEETSSHEET 1.

WIT/YISSESE S. G. DAVIDSON.

GENTRIFUGAL PAN. APPLICATION FILED MAY 23, 1913.

1,11 1,250, Patented Sept. 22, 1914.

2 SH EETSSEBBT 2. .g' \1 a i Y J UNITED STATES PATENT. o FroE.

.smUEL CLE'LAND nnvrnson, or nnnrssr, IRELAND.

onn'rnrroenn FAN.

. I 4 v Specification of Letters Patent. Patented Sept. 22, 1914 Application filed May 23, 1913,. Serial ho. 769,362.-

To. all whom it may concern: Be it known. that I, SAMUEL CLELAND DAVIDSON, of Sirocco Engineering Works,

Belfast, Ireland, have invented certain new anduseful Improvements in or Relating to Centrifugal" Fans, of which the following is a specification.

This invention relates to centrifugal fans of the kindwhich formsthe subject-of my,

. fan. wheel from, said space both centripetally and axially, while the positive parts or ends of the. blades are exposed to the space into which said air is circumferentially discharged, and means are provided in the form of a partition 'in the space surrounding the fan wheel which so divides the space outside the periphery of the fan wheel as to prevent the. discharged air from returnmg to thespace 'from which it is drawn. 4 v According to the present invention, apartition iscarried by or forms part of the fan wheel itself.. It may extendoutward from theeriphery, and it may also extend in, war through the blades for a suitable distance toward the axis. In some cases the inner edge. or portion ofthe partition or the outer edge or portion, or both edges,'may be curved or bent over to better direct the flow,

of air into, throughor'imm the fan. The

. titionmounted outside the fan wheel. Theblades of the fan wheel may in some partition carried uponfthe fan wheel will generally meet or overlap another fixed-parcases witlnadvantage be formed in parts or i, halves, secured. toeach side of the partition.

In some cases I employ a form of fan wheel consistlng of a large number of blades, long i axially and short radially, in combination with a certain number of radially deep which extend inward radially or in suitable curves tothe hub or boss'of the fan wheel, and these blades may extend axially for the full. depth of the intake chamber, or

- t e fee Yfor only part of the axial depth thereof, and their edges may be suitably shaped'to suit the mounting, dimensions, andpOSiliiOn of The position of the partition 2 may be varied according to requirements for example it may be located centrally of the fan wheel blades at the neutral point thereof or may be located nearer to the ends of the blades either on the positive or discharge side of the. negative or intake side.

Referring to the drawings :Figure 1 is .a vertical section of one construction embodying the invention; Figs. 2 and 3 are respectively vertical section and side elevation of a fan Wheel similar to Fig. 1 fitted with a casing; Figs. 4:, 5, 6 and 7 are similar views to Fig. hshowing modified constructions; and Fig. 8 is a front elevation of the fan wheel shown in Fig; 7 Figs. 9, il'O, 11, 12 and 13 illustrate modifications showing the bending or curving of the. in-

ner edge, the outeredge and both edges of the partition. l I

ReferringtoFigs. 1, 2 and 3, the partition '2 is here fixed to and forms part or the fan wheel a. Said partition is situated about half way between the ends of the fan wheel blades and extends from the inner edges of y [said blades outward beyond the peripher and overlaps a -fixed partition 2' whic .serves to direct the air discharged-from'the positive portionof thefan wheel and to. prevent same from returnin to the negative side of the blades- It w' be seen that in all the fans illustrated the air enters both axially and centripetally into the intake .chamber '11 and is discharged from the positive portion of the blades on the opposite'side of the partitions z a as indicated by the arrows. It will be readily Qb'. ,vious that if thepartition z' is extended 'out ward, a portion of the. partition 2 maybe dispensed with.

In Fig.1 the fan wheel is supposed to be acting as a wall fan, of which the partition f e' eitherforms the wall or is attached thereto,- while inFigs. 2. and3 the positive part of the fan wheel discharges into a spiral casing a which is preferably made deep in a radial direction-as indicated, the negative portion of the blades protruding out from the casing into the space from which the airis drawn. A. shield plate p may extend over the protruding end of the fan wheel.

Fig. 4 shows. a modification wherein the partition-a is not centrally disposed, but is mounted more toward the negative ends of the blades, the positive or discharge portion .9? the anwheel blades i g ther y in-' creased 1n axial length relative to the negative portion. The partition 2 'ma-yif desired be nearer the positive ends of the blades than the negative ends in which case the positive or discharge portion of the fan wheel will be decreased instead of increased.

Fig. 5 shows a similar construction to Fig. 4 wherein the partition 2 is. carried inward beyond the inner edges of the blades.

Fig. 6 shows a modification where the partition a only extendsinwa-rd as far as the outer edges of the fan wheel blades.

Figs. 7 and-8 show'a further modification having a partition 2. similar to hat shown in Fig. 6 wherein the fan whee is not only provided with axially'long blades such as described in prior Patent No. 66239.5 dated 27th November, 1900,. but is also pro- .vided with a certain number of radially deep blades e which extendinwa-rdto the hub or boss of the fan wheel, the radial edges of these blades may be variously formed, for example they may take the formation shownin the elevation, Fig. 7, at e, and the said blades instead of being 'straight or'flat as shown maybe suitably curved asis usual with blades of this kind. The partition as shown in Fig. 7 extends only from the. periphery of the bladesoutward; but, in this same construction, thepa-rtition a may be extended to the inner. edge of the series of radially narrow blades as indicated in Figs. 1 and 4, orwithintheir inner edges as indicated in Fig.5..

In Fig.- 9 is illustrated a construction wherein the inner edge of the partition is curved or bent toward the intake. In Fig. 10 the outer edge of the, partition is illustrated' as being bent in the opposite direction whereas in Fig. 11 I-have illustrated a construction. embodying the said curves at both edges of the partition.

Although the drawings show the multibladed drum type of fan, it is to be understood that the partition 2: shown may be applied to all those types of fan wheel as are specified in my said prior application for patent Serial No. 722,220/12.

What I claim and desire to secure by LettersPatent is 1. The combination with a centrifugal fan wheel having an axial intake of apartition carried by the fan wheel and disposed about the neutral part of "the fan wheel blades, the negative part of the fan wheel on one side of the partition being exposed to the space from which the air is drawn whereby the air enters the fan wheel both axially and centripetally and the positive part of the fan wheel being disposed on the other side of said partition and discharging the air circumferentlally.

2. The combination wlth a centrifugal fan wheel having an axial intake of a partition carried upon the fan wheel and forming part thereof, said partition being disposed between the ends of the fan wheelblades so as to separate the negative and the positive portions of the blades, the negative part of the fan wheel which is on one side of said partition being exposed to. the space from which the air-is drawn,wherebythe air enters the fan wheel both axially and centripetally, and the positive part of the fan wheel being disposed on the other side of said partition and discharging the air circumferentially.

3. The combination with a centrifugal fan wheel having an axial intake of a partition carried by the fan wheel and disposed about the neutral part ofthe fan wheel blades, the negative part of the fan wheel on one side of the partition being exposed to the space from which the air is drawn and whereby the air entersthe fan wheel both axially and centripetally and the posi: tive part of the fan wheel being disposed on the other side of said partition and discharging the air circumferentially, and an external fixed partition encircling the fan wheel and forming an extension of't-he partition which is on the fan wheel.

4. The combination with a centrifugal fan wheel having an axial intake ofa par tition carried upon the fan wheel and forming part thereof, said partition being disposed between the ends of the fan wheel blades so, as to separate the negative and 5 the positive portions of the blades, the negative part of the fan wheel which is .on one side of said partition being exposed tothe space from which the air is drawn, whereby the air enters the fan wheel both axially and centripetally', and the positive part of the fan wheel being disposed on the other side of said partition and dischargingthe air circumferentially, and an external fixed partition encircling the fan wheel andform; ing an extension of the partition which is on thefanwheel.

5. The combination with a centrifugal fan wheel having an axial intake of a. partition carried by the fan wheel and disposed about the neutral part of the fan wheel blades,- said artition'extending inward. tothe in- 115 ner e ges of the 'fan wheel blades, the negative art of the fan wheel on one sideof the partition being exposed to the space from which the air is drawn whereby the air en'-' 'ters the fan wheel both axially-and cen- 6.'-The com'binat1on with a centrifugal fan wheel having an axial intake ofa partition carried by, the fan wheel and disposed about the 'neutral part of the fan wheel blades, sa dpartiti0n extending inward to and beyond theinner edgesof the fan wheel blades,

7. The combination with a centrifugal fan wheel having an axial intake of a partition carried by the fan wheel and disposed about the neutral part of the fan wheel blades,

said partition extending outward from the periphery of the fan wheel blades, the negative part of the fan wheel on one side of the partition being exposed to the space from WlllCh the air is drawn whereby the air enters the fan wheel both axially and centripetally, and the positive part of the fan wheel being disposed on the other side of said partition and discharging the air circumferentially 8. The combination with a multi-bladed centrifugal fan'wheel of the drum type having an axial intake and having some of the blades carried inward to about the axis, of a partition carried by the fan wheel and disposed about the neutral part of the fan wheel blades, the negativepart of the fan wheel on one side of the partition being exposed to the space from which the air is drawn whereby the air enters the fan wheel voth axially and centripetally, and the positive part of the fan wheel being disposed on theother side of said partition and dischaging the air circumferentially.

9.. The combination with a centrifugal fan wheel, having blades and having a substantially uniform diameter throughout the length of the blades, of a partition carried by the fan wheel and disposed between the ends of said blades, the negative art of each of said blades on one side of t e'partition being exposed to the space from'which the air is drawn and the positive part of said blades on the other side of the partition being exposed to the space into which the air is discharged, and said fan having an axial intake whereby the air is taken in radially along and centripetall through the negative'parts of said bla es and is discharged 'centrifugally through the positive parts thereof.

In witness whereof, I have hereunto signed my name in the presence of two subscribing witnesses. I

SAMUEL GLELAND DAVIDSON.

I Witnesses:

JOHN JOHNSON, 4 Elven TAYLOR Comma. 

